Automatic train-control mechanism



Feb. 24. 19.25. 1,527,516 J. L. HAYTER ET AL AUTOMATIC TRAIN CONTROL MECHANISM Filed Dec. 21, 1922 5 Sheets-Sheet 1 Feb. 24. 1925. 1,527,516

J. L. HAYTER ET AL AUTOMATIC TRAIN CONTROL MECHANISM Fil ed Dec. 21, 1922 5 Sheets-Sheet 2 Feb. 24 19.25.

J. L. HAYTER ET AL AUTOMATIC TRAIN CONTROL MECHANISM I Filed Dec. 21, 1922 5 Sheets-Sheet 5 Feb.

J. L. HAYTER ET AL AUTOMATIC TRAIN CONTROL MECHANISM Filed Dec. 21, 1922 5 Sheets-Sheet 4 Feb. 24. 19.25. 1,527,510

J. L. HAYTER ET AL AUTOMATIC TRAIN CONTROL MECHANISM &

Patented Feb. 24, 1925.

JOHN L. HAYTER AND RUSSELL. C. BENNETT, OF NEW BRUNSWICK, NEW JERSEY,

PATENT OFFICE.

ASSIGNORS T GEORGE E. MCCORMICK, OF NEW BRUNSWICK, NEW JERSEY.

AUTOMATIC TRAIN CON TROL MECHANISM.

To all whom it may concern:

Be it known that we, JOHN L. HAYTlgR and RUSSELL C. BnNNn'rr, citizens of the United States, residing at New Brunswick,

I in the county of Middlesex, in the State of- New Jersey, have invented certain new and useful Improvements in Automatic Train- Control Mechanisms, of which the following is a specification. t

The invention relates to an improvement in automatic train control mechanisms designed to reduce the speed of the train or to bring it -to a full stop according to the condition of the track as indicated by the electric 1| block signal system with which the railway is equipped. More particularly the invention is an improvement on the automatic train control mechanism described and claimed in copending application, Serial No. 90 57 9,564, filed August 4, 1922.

The automatic train control mechanism disclosed in that application comprises a three-position valve which is arranged to connect the train brake pipe with either a relatively small vent or a relatively large vent, according to road conditions, and bring about a service or an emergency application of the brakes The devicesfor controlling the operation of the three-position valve are set in operation by a two-pole magnet located inthe road bed of the railway and connected with the block signal system. Inthe present invent-ion a ramp rail is substituted for the two-pole track magnet and II the valve cont-rolling devices are modified accordingly; 1

One feature of the present invention is to arrange the wires connected with the means for controlling the operation of the valve 0 so that if there has been an automatic service application of the brakes in response to track conditions and the engineer-ignores the situation and the train runs by the caution signal and enters the next block, there 0 will be an automatic" emergency application of the brakes. "Other features ofi the present invention will be pointed out as the description proceeds.

The present train control mechanism opervlo ates like the mechanism of said application to reduce the speed of the train in one block, then if the road conditions which resulted in the reduction of the train speed still persist in the next succeeding block, to bring the train to a full stop. There is a service application of the brakes under caution condltlons at whatever speed the train enters the caution block, whether at high speed or at aspeed below that to which a service application of the brakes usually reduces the train. Moreover, the train control mechanism of the present invention is adapted like the mechanism of said application for use in conjunction with a three-position signal system in which the signal is controlled by arelay box having polarized contact points and with a three-position signal system in which the contact points of the relay box are non-polarized. Where the train control mechanism is used in connection with a. polarized signal system, the automatic control of the train is partly in response to actual road conditions as indicated by the signal system as a whole and partly in response to road conditions as indicated by the signal orsemaphore. Where the train control mechanism is used in connection with a non-polarized signal system, the control of the train is 'efiected by actual road conditions as indicated bythe signal system, irrespective of the position of the signal or semaphore. 1

Inthe accompanying drawings illustrating the preferred form of the invention, Fig. 1 is a section through the three-position valve for controlling the: train brake pipe and through the means for actuating the valve. The means for controlling the operation of the valve is illustrated artly in section and part1 diagrammaticz ly; Fig. 2' is a. longitndina section through the valve parts showing their position when the train brake pipe is connected with the emergency,

vent, the electric connections of the valve controlling means being indicated diagrammatically; Fig. 3 is aview similar to Fig. 2 with the parts in position when the train brake pipeis connected with the service vent; Fig. 4 is a sideelevation of the shoe carried by the train in position to contact with the ramp rail, thereby connecting the signal system with the train control mechanism; Fig. 5 is a top plan ot the engineers valve; Fig. 6 .is a diagram of a block signal system employing a non-polarized circuit, showing the connections between the system and the ramp rail of the train control mechanism; and Fig. 7 is a transverse section, on

an' enlarged scale, through a modified form of shoe and ramp rail, with the means for controlling theoperation otthe valve and the block signal system shown diagrammatically.

The improved train control mechanism of the present invention comprises a double ramp rail located in the road bedof the railway, preferably on the outside of one of the tracks in advance of the block with which it is connected and whose track condi tions are to control the: oncoming train through the block signal system and the ramp rail. The ramp rail is directly con 1.5 nected with whatever signal system the railway is equipped with. 'The part of the train control mechanism carried by the train comprises two solenoids and their armatures for cbntrolling the operatioirof the three-position valve, and the initial energization of, the sol enoidsis effected from the battery of the block signal system when acaution or an emergency condition exists inthe block. The double ramprail is employed to momentarily connect the battery of the block signal system with the solenoids. If a caution condition exists in the block, the

14 with an emergency vent 15 and with a servicevent 16. Under normal conditions the upper end of the train brake pipe 14 is closed by a ball valve 17. When an emergency condition exists in the block, the piston 12 is moved to the left, as shown in Fig. 2, thereby connecting the train brake pipe14 with the emergency vent 15 through the space 13 and causing the piston head 18to lift the ball valve 17 out-of its seat. Thereupon the brakes are set to bring the train to an immediate and complete stop. When a,

caution condition exists in [the block, the piston 12 is moved to the right, as shown in Fig. 3, and the piston head 19 lifts the ball current will flow through one section of the ramp rail, and thus bring about the energiza'tion ot one of the solenoids; and if an emergency condition exists in the block, the current will flow through the other section of the ramp rail and thus bring about the energization of the other Solenoid. The

. parts are so arranged that if the track conditions in the block require an emergency application of the brakes, this will be automatically effected by the train control mechanism whether or not the signal or sema- 40 phore indicates that condition. Whether a service application of the .brakes will be controlled directly by the actual track conditions or willbe controlled by the track.

conditions as, indicated by the position of the signalwill depend upon the type of block signal system' with which the railway is the automatic service application of the brakes will depend upon the opera-tionof the next succeeding signal. But where a non-polarized block signal system is used, then the service application of the brakes will be controlled directly by track conditions as indicated by the signal system.

The train control mechanism will be described in connection with both these standard block signal systems.

05 In the illustrated embodiment of the in valve 17 so as to permit the air to escape from the train brake-pipe 14 through the service vent 16 and bring about a service application of the brakes to slow 'the train down. A

If the track conditions automatically effeet the operation of the three-position valve 12 either to cause a service or an'emergency application of the brakes, and, the engineer turns thehandle 20 of the engineers valve 21 to either service or emergency position (as will be explained more fully hereinafter), the three-position valve will be restored to normal position.

:The actuation of the three-position valve 12 of the train control mechanism is governed by 'two valve solenoids 23 and 24 1whiclh control the passage of compressed air to themeans for operating the valve- The valve solenoid 23 is mounted on the end of a cylinder 25, bolted to the flanged end 26 of cylinder 11, and the valve solenoid 24 is mounted on the end of the cylinder 27, 'bolted'to the flanged end 28 of cylinder 11. Connected to one end of valve 12 and sliding within cylinder 25 is the piston 30, and connected with the other end" of the valve and sliding within cylinder 27 is the piston 31.

Two compression springs 32 and 33 are interposed between the'ends of the valve and the plates 34 to hold the valve in normal position, as shown in Fig. 1. I

. The pistons .3tl and 31 are moved to actuate the valve by means of compressed air, which is admitted to piston 30 through the valve 35,-and to piston 31 through the valve 36. The solenoid 23 and the valve 35 are exactly the same in "construction as the solenoid 24 and ithe valve 36. The construction of only one sole oid and one valve will therefore be describe When the solenoid 23 is energized itdraws the armature 38 downwardly, thereby unseating the valve 39 which is connected with the lower end of the armature stem 40. This permits compressed air to pass through the opening 41 into the cylinder 25 and move the valve 12 to the right, as shown in Fig. 3. The downward movement-of the armature 38 causes the valve 42 formed on the armature stem 40 to close the relief-opening 43. When the solenoid is deenergized by the breaking of its circuit, the spring 44 raises the armature 38 to normal position, thereby causing the valve 39 to seal the opening 41 and the valve 42 to unseal the relief opening 43 to permit the air to escape and the valve 12 to return to normal position. In like manner, energization of solenoid 24 results in the piston 31 and valve 12 moving to the left, as shown in Fig. 2. Y

The solenoids 23 and 24 are located in normally open circuits. When these circuits are closed, the solenoids derive their energy from the battery 46.- These circuits are closed by means for controlling the 'op eration of the three-position valve. This means comprises two armatures forming part of the solenoids 49 and 50, which are housed in a casing, not shown in the drawing. The solenoid 49 is energized. when a caution condition exists in the block the ,train is approaching, and the solenoid 50 is energized when there is an emergency condition in the block. When a caution con-' dition exists in the block and the caution solenoid 49 is energized, the armature .47, carrying the bridges 51 and 52, is moved to the right, thereby bridging the contact points '53 and 54, and 55 and 56, respectively,

as shown in Fig. 3, and closing the circuit in which the solenoid 23 is located. When an emergency condition exists in the block,

the emergency solenoid 50 is energized and the armature 48 carrying the bridges 59 and 60 is moved to the left, thereby bridging the contact points 61 and 62, and 63 and 64,

respectively, (Fig. 2) and closing the circuit in which the solenoid 24 is located. The armatures 47 and 48 are returned to normal position by the springs 57 and 58, respec-- tively, (see Fig. 7).

The initial energization of the solenoids 49 and 50 is derived from the battery 65 of the. block signal system. The connections between the battery 65 and the solenoids 49 and 50 comprise a double shoe 66 (Figs. 4

and 1) carried by the train and a double ramp rail 67 located beside the road bed of the railway. The ramp rail 67 comprises the sections 68 and 69 which correspond to the shoe sections 70 and 71, respectively. The shoesections are .pivotally connected at the lower end of a spring-pressed plunger 73 mounted in a housing 74 supported from the side of one of the cars, preferably the tender. Acompression spring 75 acts to press the plunger and shoe downwardly so that the latter will make a good contact with the ramp rail. -A screw 76 limits the downward movement of the plunger and shoe.

.track. the circuit is traced from the battery 65 (Fig. 1) to the solenoid 49 through the switches 81 and 82, the wire 83, the ramp rail sections 68, the shoe section 70, the plunger part 78, and. the wire 84. From the solenoid the circuit continues through the wire 85 which is connected with a part of the tender, whence the current passes back to the battery through truck 86, the track 87 and wire 88. This circuit is closed only as long asthe shoe is in contact with the ramp rail. This contact is suflicient to cause an initial energization ofthe solenoid 49 to bridge the contact points 53 and 54, and 55 and 56 (Fig. 3.) The bridging of the points 53 and 54 causes the solenoid 49 'to be permanently energized from the battery 46. The circuit from the battery 46, to solenoid 49 is traced from the positive side of the battery through wire 89 to the handle 20 of the engineers valve and the are 91. From the are 91 the circuit continues through the wire 92 to the contactpoint 93 andfrom thence through the bridge 59 of the armature 48 to the contact point 94. From the point 94 the circuit continues through the wire 95, the contact point 53, the bridge 51 of armature 47, the point 54, and the wire 96 to the solenoid. From the solenoid the current passes to the negative side of the battery 46 through the wire 85. The circuit as thus traced is broken when the engineer moves the handle 20 of his valve to service position, which is indicated by the dot and dash line. 97 in Fig. 5: and also when the "emergency solenoid 50 is energized, thereby moving the"bridge 59 out of contact with the points 93 and 94.

lVhen there is an emergency condition in the block, the circuit fromthe signal batter 65 to the emergency solenoid 50 is traced through the switch 81, the wire 99, the ramp rail section 69, the shoe section 71, the plungei' part 79 and the Wire 101. From the solenoid the current returns through the wire 102 to the truck 86 and from thence by the rail 87 and wire 88 to the negative side of 63 and 64, respectively, as shown Fig. 2. The permanent energization of the solenoid .50 is secured through a circuit .which is traced as follows :-From the positive side of the battery 46 the current passes through the battery. The'solenoid remains permanently energized until the engineer shifts the handle 20 vof his valve .to theposition indicated by the dot-and dash line 107.

When the caution armature 47 is actuated and the bridges 51 and 52 span the points 53 and 54, and 55 and 56,. respectively, the circuit in Which the solenoid 23 is located is closed, (Fig. 3). This circuit is traced from thepositive side of the battery 46 through the wire'89, the are "91, the wire 92, the wire 109, the bridge 52 and the wire 110 to the solenoid 23. From the solenoid, the current returns through the wire 111 to the negative side of the battery. When the emergency armature 48 is actuated and the bridges 59 and 60\span the contact points 61 and 62, and 63 and 64, respectively, the circuit in which the solenoid 24 is located is closed, (Fig. 2). This circuit is traced from the positive side of thebattery 46. through the wire 89, are 103, wire 104, wire 108, the bridge 60 and the wire 112 to the solenoid 24. From the solenoid the current returns tion solenoid 49. From the solenoid thec urren't returns through the wire 115' and the wire 116 to a pin 117 inserted in the side of the plunger part 78 and insulated there-.

from. The inner end of the pin 117 contacts 1 with an insert 118 insulated from the plunger parts 78 and 79 and arranged to support a middle shoe 119, which is adapted to contact with a middle ramp rail 120. From the middle ramp rail 120 the current returns to thebattry through the wire 121. When the modified forms of shoe and ramp rail are used and an emergency condition exists on the track, the current will flow from the battery 65 to the emergency solenoid 50 through the switch 81. the wire 99. the rail section 69. the shoe section 71, the plunger part79and the wire 101. From the solenoid the current returns to the battery, through the wire 122. the wire 116. the pin 117, the shoe section 119. the ramp section 120 and the wire 121.

A block signal svstem having a single rela with polarized contact points is illustrated diagrammatically, in the usual manner, in the lower left hand corner of Figs. 1 and 7. The tracks are indicated at 124 and 125.- The pole-changer is shown at 126. I

Under normal conditions the current passes from the positive side of the battery 127 through the switch 128, wire 129 to track 125,

and thence through wire 130 the relay box 131. From the relay box the current re- 35 through the wire 113 to the negative side oiturns through the wire 133. the track 124,

the battery. By passing-the circuits whic tively, it will be seen that the shifting of the handle 20' of the engineers valve to the positions indicated by the lines 97 and 107 breaks the circuits 'throughthe solenoids 49 and 50 and permits the parts connected with the valve 12 to be restored to normal position.

i In case the train control mechanism of the present invention is installed on a railroad which requires the use of the wiring system.

with which its signal system is equipped and will not permit a current to be returned through the train to the signal battery, the present invention provides a modified form of shoe and ramp rail bywhich the current is returned from the caution and emergency solenoids to the signal battery. This moditied form of shoe and ramp rail is illus tratedin section on an enlarged scale in Fig. 7. The parts of the modified shoe and ramp rail which are the same in construction and functi on'as the corresponding parts of the shoe and ramp rail shown in Figil are given r the same reference numerals. modified forms of shoe and ramp rail are lVhcn these used, and caution conditions exist on the track, the current flows from the batte 65 through'the switches 81 and 82, the .wire 83,

thewire 134 and the switch 135 to the negaand the switches 82 and 140 are in engage-v ment with the contact points 141 and 142. The points 138 and 139 are in circuit with the solenoid 145 which controls the caution position of the signal 143Qand the points 141 and 142 are in circuit with the solenoid 149 which controls the clear position of the signal. The circuit of thecaution position solenoid is made i from the battery 65 through the switch 81, the contact point 138 'and the wire 144 to the solenbid 145. and from the solenoid through the wire 146, the contaict point 139, the switch'137 and the wire 147 to the negative side of the battery. The circuit of the clear position solenoid is made from the positive side'of. the battery through the; switches 81 and 82, the contact point 141 and the wire 148 to, the solenoid .149. andfromthe solenoid through the wire 150, the contact point 142, the switches 140 and 137 and the wire 147 to the negative side of the battery. T Thuswhen the pole changer 126 is in normal condition the signal v connect the solenoids 49 and 50 with the bati fivei side of the battery. Under these contery 46 through the arcs 91 and 103, respecand 153, respectively, as will be explained below. owing to the fact that a train has passed into the next block which is marked Z. the polarity of the ,contact points in the relay 131 is changed, as may be seen by tracing the circuit from the positive side of the battery 127. a.

The switches 128 and 135 of the pole changer 126 are mechanically connected with the signal 151 of block Z. When the track conditions of block Z are normal. signal 151 is in its 90 or clear position and holds the switches 128 and 135 in their normal position. When, however, a train passes into block Z, or a similarcondition exists therein, signal 151 will fall to zero or danger position and thereby swing the switches 128 and 135 into contact with the points 152 and 153, respectively. This causes the current to flow through the relay 131 in the reverse direction and makes block Y a caution block. When the train passes out of block Z the signal 151 is raised to the 45 or caution po sition and the switches 128' and 135 are thereby swung back into contact with the points 157 and 152, respectively, a ain causing the current from battery 12 to flow through the relay 131 in its normal direction. Thus it will be observed that the current from the battery 127 flows through the relay 131 in its normal direction when block Z is clear and when a caution condition ex ists therein. It is only when block Z is in danger or emergency condition that block Y is in caution condition; and it is only when block Y is in caution condition that current flows through relay 131 in the reverse direction. This is becausesignal 151 is then in zero or danger position, thereby holding the switches 128 and .135 against the contact points 152 and 153, respectively. It will be observed, moreover, that signal 151 is connected with block Z and that signal 143 is connected with block Y in which the relay 131 is located. Signal 151 influences signal 143 in that when signal 151 is picked upor raised from zero position to 45 or caution position, it swings the switches l28'and 135 back into contact withthe points 157 and," 152, respectively, so as to restore the polar-' ity of relay 131 to normal and thereby cause signal 143 to be lifted from caution to clear position. Before block Z becomes the danger block (under normal running conditions) block Y is the danger 'block and signal 143 falls to zero position is cut off from battery 127.

If there is a train in block Y the relay 131 is shunted from battery 127. The same effeet is caused by a broken rail or some similar condition. In this situation the switches 81 and 137 fall away from the contact points 138 and 139 and the signal 143 falls to its zero or stop position, as indicated in dotted lines at 155. When the train passes out of 143 to be raised to its the because relay 131 block Y (and the pole'changer 126 is again in' circuit with the relay box 131), the switches 128 and 135 are swung into contact with the points 152 and 153. This causes the switches 81 and 137 to be picked up against the points 138 and 139 and the signal 45 or caution positlon, as indicated at 156. When the polarity of the relay 131 was thus changed, the switches 82 and 140 broke contact with the points 141 and 142. When the train passes out of block Z, switches 128 and 135 will return to contact with points 157 and 152 so as to restore the relay 131 to normal polarity. The switches 82 and 140 will then swin into contact with points 141 and 142 and t e signal 143 will be restored to its 90 or clear position, as indicated in full lines.

If a train, indicated by the truck 159, enters block X and there is a train, indicated by the truck 160, in block Y, there will be an automatic emergency application of the brakes on the train in block X. The train in block Y causes the relay 131 to be shunted from battery 127, and so switches 81 and. 137 drop out of contact with the points 138 and 139. VVhen this occurs the current ceases to flow through the switches 82 and 140, although they still remain in contact with points 141 and 142. Thus the signal 143 is permitted to drop to its zero or stop position. When the switch 81 dropped out 7 of contact with point 138 it fell on contact point 162 of wire 99,,thereby establishing a circuit from battery 65, as described above, to the eme ency solenoid 50 to bring about an emergency application of thebrakes.

If train 160 had passed into block Z by the time train 159 entered block-X, there would be a service application of the brakes on train 159. When train 160-left block Y,

thereby placing the relay 131 in circuit again with battery l27, the switches81 and 137 were picked up against the points 138 and 139 and the signal .143 was raised to its 45 or caution osition. This condition of arts cause the switches 82 and 140 to be dlsconnected from the points 141 and 142 and the switch 82 to contact with the point 163 .of wire 83. This condition of the parts laces the caution solenoid 49 in circuit with Battery 65, as described above, and brings about a service application of the brakes on train 159.. 8

The connections between the two section ram rail of the present invention and a block type is illustrated diagrammatically in Fig. 6. The drawing is a conventional repre; sentation of a standard'form of the signal mechanism. It is assumed that a train rep resented by the truck 165. has passed through blocks A and B and has entered block C. This causes the current from battery 166 to be short circuited from the relay 167 signal system of the non-polarized Thereupon the switches I68, 169 and 170 fall away from the contact points 171,.172

, and 173, respectively, and the switches 17 5,

176 and 177 fall away from the points 178, 179 and 180, respectively, as will be understood by those skilled in the art, and the signal 181 will fall to zero or stop position. Dhe switches 168, 169 and 17 fall upon the dead points 182, 183 and 184, and the switch 176 falls upon the point 185 of the wire .186 connected with the ramp rail section 69,

- thereby establishing a circuit from battery vfigures will 188 to the emergency solenoid .50. The circuit is traced from the positive side of the battery through the wire 189, the switch 176, the wire 186 and-the ramp rail section 69 to the emergency solenoid, and from the solenoid back through the train 190, as described above, and the wire 191 to the negative side of the battery 188. Thus there is an emergency application of the brakes on train 190 in case it should attempt to enter block 0. p

When train 165 had left block B and enteredblock C the battery 193;became' connected again with relay 194. The wiring system of relay 194 being exactly the same as the wirin system of relay 167, the same 1 switch 170, wire 197, switch 198 and wire 199 to the rail section 68 and thence to the caution solenoid 49. From the solenoid the current will return through the train 200 and Wire 201 to the negative side of battery 196. Thus there will be a service application .of

the brakes on train 200'in case it should attempt to enter block B.

When signal 195 of block B is in caution position, signal 203 of block A will'be in its 90 or clear track position. The 90 position of the signals is controlled by the caution position of thesignal of the next succeeding block. Thus when the signal 195 of blocks B is in its 45.or caution position, the circuit from battery 196 to the solenoid 204 which controls the 90 or clear position of signal 203 is traced through wire 205,-

switch 176, wire 206, switch 177 (of block A) and wire 207 to solenoid 204. "From the solenoid the current returns to the negative side of the .battery 196 through wire 208, switch 175 (of block B) and wire 209. It

willhave been observed that the lifting of switch 176 (of block B) against the point used to designate the corre-' 179 broke the connection between battery 196 and the ramp rail. In'like manner it will be observed that the energization of solenoid 204 lifts the switch 198 (of block A) and thereby cuts off the current from battery 210 to the ramp rail. 1

The mode of operation of the various parts of the improved automatic train control mechanism has been indicated in the description of the construction of the mechanism. The mode of operation of the mechanism as a whole is briefly as follows: When the track conditions in, a block require an emergency application of the brakes on the oncoming train the current will flow from the signal battery through the ramp rail section 69 to the emergency solenoid 50. The energization of the solenoid 50 closes the circuit (as described above) in which the solenoid 24 is located. This results in the admission of air to the piston 31 and the pushing of valve 12'to the left,,as shown in Fig. 2, to connect the train brake pipe .with the emergency vent 15. If the track conditions require a service application of the brakes, current will flow from the signal battery through the ramp section 68 to the service solenoid 49. The energization of solenoid 49 closes" the circuit in which the solenoid 23 is, located and this results in the admission of air to piston 30 and the pushing of valve 12 'to the right, as shown, in Fig. 3, thereby connecting-the train brake pipe 14 with the service vent 16. For convenience, the automatic emergency application of the brakes has been described as preceding the service application of the,

brakes. It will be understood, however, that in actual practice the train will pass through a caution block before it enters-an emergency block'and that, therefore, there will be an automatic service application of the brakes before there is an automatic emer- I Having thus described the invention what we claim as new is: I J

1. An automatic train control mechanism having in combinationwiththe block si'gnal system, a two-section ramp rail located in the road bed of the railway and connected with the signal system, 'the connectiohs be- 'tweeirthe signal system andwthe ramp rail being such as to cause. current to flow through 0116 880111011 when an emergency condition exists and current to flow through the other section when a caution condition exists on the track, a shoe carried by the train and having two sections corresponding to the two sections of the ramp rail, two.

solenoids connected with the shoe and arranged to receive their initial energization 2. An automatic train control mechanism having in combination with the block signal system, a two-section ramp rail located in the road bed of the railway and connected with the signal system, the connections between the, signal system and the ramp rail beingv such as to cause current to flow through one section of the ramp rail when an emergency condition exists on the track andto cause current to fiow through the other section when a caution condition exists, a shoe carried by the train and having two sections corresponding to the two sections of the ramp rail, a solenoid connected with each shoe section and arranged to receive its initial energization from the signal battery, a battery for permanently energizing the solenoids after their initial energization, a valve adapted to connect the train brake pipe with an emergency vent and with a service vent, means for actuating the valve, and means controlled by the energization of the solenoids to' control the operation of the valve actuating ,means, 4 L

e 3. An automatic train control mechanism having in combination with "the block signal system, a valve casing connected with the train brake pipe and having an emergency vent and a service vent, a valve adapted to be actuated. toconnectthe brake pipe with the emergency vent-when an emergency condition exists on the track and with the service vent .when a caution condition exists on the track, two valve solenoids for controlling the passage of compressed air to actuate the valve located in normally open circuits,

an emergenc solenoid for closing the circuit in whic one valve solenoid is located, a caution solenoid for-closing the circuit in whiclithe, other valve solenoid is located, a shoe carried by the train having two sections, one of which is connected with the emergency solenoid and the other of which is connected with the caution solenoid, a ramp rail located in the road bed of the railway and having two sections corresponding to the 7 two sections of the shoe, said ramp rail being connected with the signal system so that current passes through one section 30f the ramp rail when an' emergency condition exists and through the other section of the ramp rail when a caution condition exists on the track.

4. An automatic train control mechanism having in combination with the block signal system, a valve adapted to be actuated to connect the train brake pipe with an emergency vent and with a service vent, means for actuating the valve, an emergency solenoid' and a caution solenoid for controlling the operation of the valve actuating means, said solenoids being arranged to receive their initial energization from the battery of the signal system, connections between the sole noids and the signal battery, a battery carried by the train arranged to permanently energize the solenoids'atter they have been initially energized by the signal battery, the emergency solenoid being arranged when energized to break the circuit in which the caution solenoid is located.

5. An automatic train control mechanism having in combination with the block signal system, a valve adapted to be actuated to solenoids and the silgnal battery and the circuits between the train battery and the solenoids, the movement of the emergency solenoid armature serving to break the circuit between'the train battery and the caution solenoid. 1

6. An automatic train control mechanism having in combination with the block signal system, a valve adapted to be actuated to connect the train bralge pipe with an emergency vent when emergency conditions exist on the track and with a service vent when caution conditions exist oi the track, means for actuating the valve, two valve solenoids for controlling the operation of thevalve actuating means, said solenoids being located in normally open circuits, an

emergency solenoid and a caution solenoid.

tially energized by the signaLbattery, the

circuits between the emergency and caution solenoids and-both the signal battery and a the train battery being normally open and.

having in combination with the block, signal system, a valve casing connected with the trainbrake pipe and having an emergency vent and a service vent, a valve for normally sealing the brake pipe from the vents, and adapted to be actuated to connect the brake pipe with the emergency vent when an emergency condition exists on the track and with the service vent when a caution condition exists on the track, a valve solenoid for controlling the actuation of the valve to connect the brake pipe with the emergency vent, a second valve solenoid for controlling the actuation of the valve to connect the brake pipe with the service vent, each solenoid being located in a normally open circuit, an emergency solenoid for closing one circuit and a caution solenoid for closing the other circuit, the emergency solenoid and caution solenoid being arranged to receive their initial energization from the battery of the signal system, connections between the emergency and caution solenoids and the signal battery, and a battery carried by the train for permanently energizing the emergency and caution solenoids.

of the emergency solenoid arma- 8. An automatic train control mechanism having in combination with the block signal system, a two-section ramp rail located in the road bed of the railway and connected flow through the other. section of the ramp rail, a two-section shoe carried by the train and adapted to contact with the ramp rail, an emergency solenoid and a caution solenoid adapted to receive initial energization from the signal battery through the ramp rail and the shoe, a battery carried by the train for permanently energizing the solenoids after they have been initially energized by the signal battery, a three-position Valve adapted to be actuated to connect the train brake pipe with an emergency vent and with a service vent, means for actuating the valve, two valve solenoids located in nor- ,mally open clrcuits for controlling the opr eration of the val-veactuating means, bridges carried by the armatures of the emergency and caution, solenoids to close the circuits between the emergency and caution solenolds and the signal battery and the circuits in which the valve solenoids are located, the

movenientrof the emergency solenoid armattire serving to break the circuit between the train battery and the caution solenoids.

JOHN L. HAYTER. RUSSELL C. BENNETT. 

